A study of the descriptive epidemiology of tetracycline prescribing will be used to develop strategies to influence inappropriate prescribing. In January l975 the Committee on Drugs of the American Academy of Pediatrics published a position paper entitled, "Requiem for Tetracycline" which considered the problems of adverse effects in using this family of antibiotics for children less than 8 years of age. Despite the fact that complications of tetracycline therapy have been known for years and despite the warning that has been included in the "package insert" since l970, tetracycline continues to be prescribed widely for children. Indeed, in the year ending June l973, approximately l5 tons of tetracycline in liquid pediatric dosage forms alone were certified by the FDA. This study will help provide answers to questions posed by the Committee; specifically, "Who are the children receiving tetracycline syrup and drops and for what infections are these drugs being prescribed?" In addition an even more important question will be addressed: What are the characteristics of the physicians who are writing these prescriptions? Inappropriate tetracycline pescriptions for children may be considered as one of a family of tracer indicators to measure the quality of medical care in defined populations. An initial study of the recipients and prescribers of the more than 7000 prescriptions written over a two year period for ambulatory patients under 8 years old receiving care under Medicaid will detect effects of the "Requiem" article. Following this general and indirect intervention, a specific direct intervention in the form of a mailing to physician provider participants in the Medicaid program will be assessed. On the basis of these two interventions, other strategies will be generated. This study will also demonstrate the usefulness of Medicaid claims file data for intervention and follow-up monitoring. The claims file approach is innovative and provides an inexpensive data source.